Falling weight testing machines for rails

2015 ◽  
Keyword(s):  
2011 ◽  
Vol 148-149 ◽  
pp. 388-392
Author(s):  
Jie Du ◽  
Chun Ting Ma

Based on Interaction energy of solid ball, the new particle damper is designed which can be used in a high temperature and high shock energy. To verify the design of the damper, a falling weight Impact test rig is designed, a sensor, data acquisition card and computer hardware constitutes a signal test system. Experimental results show that the particle diameter is the biggest impact for the role of the particle damper , the characteristics of the displacement curves are increased at first and then decreased, the opposite effect of the time. At the same time filled with particles and the degree of damping rod embedment also have an impact on energy consumption.


1997 ◽  
Vol 1570 (1) ◽  
pp. 143-150 ◽  
Author(s):  
Lev Khazanovich ◽  
Jeffery Roesler

A neural-network-based backcalculation procedure is developed for multilayer composite pavement systems. The constructed layers are modeled as compressible elastic layers, whereas the subgrade is modeled as a Winkler foundation. The neural networks are trained to find moduli of elasticity of the constructed layers and a coefficient of subgrade reaction to accurately match a measured deflection profile. The method was verified by theoretically generated deflection profiles and falling weight deflectometer data measurements conducted at Edmonton Municipal Airport, Canada. For the theoretical deflection basins, the results of backcalculation were compared with actual elastic parameters, and excellent agreement was observed. The results of backcalculation using field test data were compared with the results obtained using WESDEF. Similar trends were observed for elastic parameters of all the pavement layers. The backcalculation procedure is implemented in a computer program called DIPLOBACK.


Author(s):  
Angel Mateos ◽  
John Harvey ◽  
Miguel Millan ◽  
Rongzong Wu ◽  
Fabian Paniagua ◽  
...  

The capacity to resist flooding is one of the critical challenges of pavement resiliency in locations subject to inundation. Flooding increases moisture contents, which weakens most pavement materials. Although the effect of moisture on the mechanical properties of most pavement materials is reversible, the structural damage caused by trafficking applied on the weakened pavement structure is not. The critical time for structural damage is typically after the flood and before “life-line” pavements have dried back when trucks are bringing in relief supplies and hauling out demolition. This fact, together with the increased occurrence of extreme weather events and sea level rise resulting from climate change, emphasizes the need to better understand the impacts of flooding on identified life-line pavements. This paper evaluates the flooding resiliency of thin concrete overlay on asphalt (COA) pavements by studying the effects that water saturation produces on the pavement structure. The research is based on the structural response and distresses measured in five thin COA sections that were instrumented with sensors and tested with a heavy vehicle simulator (HVS) under flooded conditions. The research shows that the flooding did not produce a noticeable change in the structural capacity of the COA, based on the structural response measured under the loading of the HVS wheel and the falling weight deflectometer, but did result in some structural damage to the asphalt base in some of the sections.


Sign in / Sign up

Export Citation Format

Share Document